The studies proposed here flow directly from research conduced during two previous stages of funding. In the initial stage (1988-1990), we studied the effects of student use of INQUIRER, a fact and text base in bacteriology. In the second (1990-present), we examined the relationship between student's searching proficiency and their personal knowledge in the domains of bacteriology, pharmacology, and toxicology. In the third phase, described here, we will create and study the efficacy of significant extensions of our existing INQUIRER in microbiology and pharmacology. Whereas our previous research involved the use of computer- based educational resources during the preclinical years only, in this phase we will also study these resources as integrated into the clinical years of medical education. Our third phase of research has the following specific aims to be addressed over four years: l) To explore in greater depth the relationship between domain knowledge, searching proficiency of a fact and text base, and problem solving proficiency across three biomedical domains. This work is, to a significant extent, a replication of the research design of our second phase, using an additional cohort of students. However, in these studies students will be using a graphical user interface as opposed to the form- oriented interface of the previous INQUIRER. 2) To study what form of information resource better serves the needs of learners at differing levels of experience. We will address this question by creating two versions of the application: one with a fully articulated hypermedia environment and another with only a Boolean searching capability analogous to existing INQUIRER. We will compare students using these two different versions, when their personal knowledge is low and also when it is relatively high, to determine whether and at which time one format is superior in helping students solve problems. 3) To explore in detail how students use an information resource to solve clinically oriented problems. To this end we will create a series of clinical simulations and an enhanced INQUIRER available to students as a resource which is easily accessible as they work through the simulations as part of their clinical clerkship in internal medicine. We will construct influence diagrams that allow us to evaluate objectively each student's performance on these simulations. This will enable us to study when and with what effect students can enhance their performance on clinical case problems with aid from a structured information resource.